So you've contracted a virus that's taken over your computer, and you can't even boot up to try and troubleshoot the problem. The solution: Create a rescue CD, boot into a safe environment, and rid your PC of any nefarious software while it sleeps. Here's how to do it with minimal effort.

This year, a new product called the FixMeStick came out that makes virus eradication dead simple. With just a couple of clicks, you can boot using your FixMeStick so that it can attack the viruses while they're inactive, leaving them defenseless. The only problem: the FixMeStick costs $59.99, which is more than most people are willing to spend.

Luckily, you can easily create your own FixMeStick-like rescue disc with just a blank CD and one of many free programs. Here, we'll show you how to put one together and use it to eradicate any viruses on your system.

Note: This is meant to be a beginner's guide to system rescue. If you're an experienced user, you may prefer to use something like Hiren's BootCD, which contains a ton of other diagnostic tools you can use to figure out what's wrong with your computer and retrieve important data. For the purposes of this guide, though, we're trying to make it as simple as possible, so anyone can get the job done with minimal effort. If you're already familiar with the process, be sure to send it to your friends and family so they can be too!

How to Create Your Rescue Disc

If you can't boot into your computer, you'll need to borrow one from a friend to burn your rescue disc, but other than that, all you really need is a blank CD. Here's what you need to do:

Insert a blank CD or DVD into your computer, and double-click on the Rescue System installer that you downloaded. Pick your disc drive from the list, and it will install the rescue disc for you. Note: If you don't have a CD drive, you can download this Avira Rescue ISO from this page instead, and use Unetbootin to create a bootable flash drive instead. It takes a bit more work, but it'll work on computers that don't have a disc drive.

Once your disc has finished burning, insert it into the affected computer and press the power button. If it boots into the Avira Rescue System interface, skip to the next section.

If your computer doesn't boot into the Avira Rescue System interface, you'll need to tweak a setting in your system's BIOS. To do so, reboot your computer. When it first boots up, you should see a screen that says something like "Press DEL to enter setup." Press and hold the key it requires to enter setup. Everyone's computer is different, but somewhere in those menus you should find an option that says something like "Boot Order." Change that setting so that your CD drive is number one on the list, save your settings, and exit. When you reboot, you should find yourself in the Avira Rescue System.

How to Scan Your Computer with Your Rescue Disc

Now that you've successfully created your rescue disc, it's time to clean out that infection. Once you've booted into the Rescue System, here's what you need to do:

When you first boot up, Avira will ask you if you want to boot into the AntiVir Rescue System. To do so, type 1 and press Enter. It will then go through the process of booting.

When it's done, you should be greeted with the screen at the right. You can browse around the Configuration if you want, but you should be fine with the default settings. Just go to the "Virus Scanner" tab and click "Start Scanner" in the bottom left-hand corner.

As the scanner runs, it should repair any infected files it finds. When it's done, reboot your system and see if you can boot back into Windows. With any luck, Avira should have done its job and you'll at least be able to get back into your system.

If you're still having problems after running your rescue CD, you may need to take more drastic measures. However, if your rescue CD worked and you can boot your computer up correctly, you're almost home free. You should probably run your regular antivirus program to see if there's anything else left on your system, and clean up any malicious files it finds.

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Once you get everything running properly, it's time to think about long term protection. After all, you don't want to have to do this again. Make sure you have a good antivirus program running at all times. You don't have to pay money for one, either—Microsoft Security Essentials is more than good enough. While you're at it, you should set up a simple backup system so you never lose your important files to a virus or other disaster again.

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